var $j = jQuery.noConflict(); 
	var preSelected;
	//var nav=$j(div + a);
	//alert(nav[0].href);
	$j(function(){
		var nav_a=$j('#page_nav a');
		var nav_span=$j("#page_nav a span");
		var url = (GetCookie("url")==null) ? nav_a.get(0) : GetCookie("url");

		for(var u = 0 ;u<nav_a.length;u++){
			if(nav_a.get(u).href == url){
				nav_a.get(u).style.backgroundPosition="0% -42px";
				nav_span.get(u).style.backgroundPosition="100% -42px";							
				break;
			}
		}
		nav_a.bind("click",function(){
			SetCookie("url", this.href);
		}
		);
	});

	function setSelected(obj){
		var h=obj.href;
		alert(h);
	}
	function SetCookie(name, value){
		//alert("set cookis");
		var expdate = new Date();
		var argv = SetCookie.arguments;
		var argc = SetCookie.arguments.length;
		var expires = (argc > 2) ? argv[2] : null;
		var path = (argc > 3) ? argv[3] : null;
		var domain = (argc > 4) ? argv[4] : null;
		var secure = (argc > 5) ? argv[5] : false;
		if(expires!=null){
		expdate.setTime(expdate.getTime() + ( expires * 1000 ));
		}
		document.cookie = name + "=" + escape (value) +((expires == null) ? "" : ("; expires="+ expdate.toGMTString()))+((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain))+((secure == true) ? "; secure" : "");
	}
				
	function GetCookie(name){
		//alert("get cookie")
		var arg = name + "=";
		var alen = arg.length;
		var clen = document.cookie.length;
		var i = 0;
		while (i < clen)
		{
		var j = i + alen;
		if (document.cookie.substring(i, j) == arg)
		return GetCookieVal (j);
		i = document.cookie.indexOf(" ", i) + 1;
		if (i == 0) break;
		}
		return null;
	}
				
	function GetCookieVal(offset)
	//获得Cookie解码后的值
	{
		var endstr = document.cookie.indexOf (";", offset);
		if (endstr == -1)
		endstr = document.cookie.length;
		return unescape(document.cookie.substring(offset, endstr));
	}
				